Moner Mohammad Abu-Salha, the 22-year-old American suicide bomber who last weekend blew up an explosives-laden truck halfway across the world in Syria, played sports in Vero Beach where his parents now live and he lived at some point in Fort Pierce.

Federal authorities for most of Friday interviewed his family and friends ? some of them elsewhere in Florida ? and traced his movements, investigating whether he was recruited or radicalized online, according to the Miami Herald

Photographs posted on jihadi social media sites show the suicide bomber purportedly in Syria, smiling and sporting a reddish-brown beard. In one of them, he is cradling a cat.

Those photos seem to match a Facebook profile for Moner Abu-Salha, who is pictured in one of his posts there standing in front of a beach. His other posts show Abu-Salha was religious and frequently mentioned prayer, God and the Prophet Muhammed. He also liked football, video games and Dunkin' Donuts.

In Syria, the suicide bomber was known by his nom de guerre, Abu Hurayra al Ameriki, or Abu Hurayra the American. The original Abu Hurayra was a companion of the Prophet Muhammed and is considered one of the most important figures in early Islamic history.

One of the two groups that claimed responsibility for the joint suicide bombing Sunday in Syria's Idlib Province, the Islamic Front's Suqour al Sham, confirmed the American's participation, according to spokesman Abu Farouk al Shami, who spoke with McClatchy via Skype. The other group involved was the Nusra Front, al-Qaida's Syrian franchise.

"It was an operation between mujahedeen from both Suqour al Sham and the Nusra Front," Abu Farouk said of the blast, which targeted a Syrian military position and included at least three bombers and tons of explosives. "Abu Hurayra was well known to us in Suqour al Sham for his kindness and bravery in combat."

Abu Farouk said that he never knew the American's real name, explaining that foreign members of Syrian rebel groups are instructed to adopt a nickname, or Kunya, in Arabic and to never reveal their actual name for security reasons.

"Their families could be targeted by police or the CIA for coming to Syria," he said. "He would never share his name or show his passport, but we knew him to be American."

In a martyrdom video released on YouTube, titled "The American Martyrdom for the Nusra Front," the suicide bomber is seen praying, playing with cats and preparing for his apparent mission. The video ends with a tremendous explosion that is said to have been from the bomb he detonated. Abu Farouk said the tape was authentic, but his claim could not be independently verified.

A statement posted online by the Nusra Front said the American took off in a truck carrying 16 tons of explosives as part of one of four coordinated attacks. The group rarely grants interviews to Western media, and spokesmen were unavailable for comment.

The U.S. government designated the group a terrorist organization in 2012, saying at the time that Nusra was an alias for al-Qaida in Iraq, which was founded by Abu Musab Zarqawi, a Jordanian, to battle the U.S. presence there. That designation was recently updated to recognize that the organization is officially seen as an al-Qaida branch operating in Syria.

The American suicide bomber's ties to Florida were first reported by CNN. The Washington Post reported he was from South Florida, and The New York Times identified him as Abu-Salha. The Times also reported that Abu-Salha traveled to Syria late last year.

The office of Florida Sen. Bill Nelson said on Friday afternoon that he had been briefed on the situation. According to his office, the Democratic senator asked broader security questions about other Americans who have reportedly been associated with groups tied to al-Qaida.

Several weeks ago, FBI Director James Comey told reporters that investigators believe "dozens" of U.S. residents may have traveled to Syria to participate in the civil war.

"With time, more people are traveling from here to there," Comey said, adding that "it's gotten at least marginally worse."

In a separate briefing, Director of National Intelligence James Clapper estimated upward of 7,500 foreign fighters have joined the Syrian war. Comey estimated that "thousands" of these fighters came from European countries.

"There is going to be a diaspora out of Syria at some point," Comey said. "And we are determined not to let lines get drawn between Syria today and a future 9/11."